The present invention is directed, in general, to battery stands and, more specifically, to a spill containment system for a composite battery stand, a method of containing electrolyte within a footprint of the battery stand and a battery stand employing the system or the method.
The traditional reliability of telecommunication systems that users have come to expect and rely upon is based, in part, on the reliance on redundant equipment and power supplies. Telecommunication switching systems, for example, route tens of thousands of calls per second. The failure of such systems, due to either equipment breakdown or loss of power, is unacceptable since it may result in a loss of millions of telephone calls and a corresponding loss of revenue.
Power plants, such as battery plants, address the power loss problem by providing the system with an energy reserve (e.g., a battery) in the event of the loss of primary power to the system. A battery plant generally operates as follows. The battery plant includes a number of batteries, rectifiers and other power distribution equipment. The primary power is produced by the rectifiers, which convert an AC main voltage into a DC voltage to power the load equipment and to charge the batteries. The primary power may, however, become unavailable due to an AC power outage or the failure of one or more of the rectifiers. In either case, the batteries then provide power to the load. Redundant rectifiers and batteries may be added to the battery plant as needed to increase the availability of the battery plant.
Space is normally a concern when constructing a battery plant. This is because it is common for a battery plant to be located on site, near the telecommunications system. The battery plant typically houses all of the batteries needed to provide power during a power outage. The tremendous amount of space necessary to accommodate the battery plants has prompted the design of battery stands capable of holding a number of batteries. Battery stands utilize the available space more efficiently by allowing the batteries to be vertically stacked.
Battery stands are typically constructed of steel members, which may be bolted or welded together to form a desired battery stand. Many different sizes and shapes of batteries may be employed in battery plants, including flooded round and rectangular cell batteries, valve regulated batteries and gel batteries. Because of the different sizes and shapes of the batteries, the battery stands must be capable of adapting to the different dimensional requirements of each battery. In response to the wide variety of batteries, an xe2x80x9cerector setxe2x80x9d type of structure was developed wherein each battery stand includes steel beam members that are bolted together to form a battery stand adapted to receive a particular battery.
Assembling a battery stand, whether at the factory or on site, generally requires a tremendous amount of time and effort. The time required to assemble a medium size battery stand may easily be two to three days. Equally frustrating problems may arise whether one orders a preassembled battery stand or one assembled on-site. Preassembled battery stands require the end user to thoroughly determine all of the requirements of the battery stand, including any constraints particular to the building in which the stand will be placed. Furthermore, the preassembled battery stands are typically cumbersome to handle and, due to their great weight, may be extremely expensive to ship. In addition to the time concerns discussed above, assembling the battery stand on site limits the end user to the parts available at the assembly site. With so many small brace members to assemble such a large structure, it is inevitable that some parts will be missing when needed to assemble a customized battery stand for a particular location.
Again, the steel battery stand has many undesirable features as well. Because the battery stand includes steel brace members, it is common for the battery stand to weigh several hundred pounds. This creates a major problem both with shipping the stand to the site, which can become very expensive, and with moving the stand within the battery plant.
Batteries housed on the battery stand may explode or leak due to, among other things, age, excessive use, manufacturing defect or abuse. The electrolyte (e.g., acid) in the batteries may be extremely corrosive, causing the steel members of the battery stand to deteriorate. When the electrolyte is spilled on the steel surface of the battery stand, the surface must typically be replaced. Due to the extensive number of batteries that may leak and the extensive number of brace members that should be removed and replaced, maintenance of the battery stand can be a time consuming and expensive process.
Further, the steel battery stand is electrically conductive and may thus create a possibility of electrical shock to those who may come in contact with the battery stand. A requirement of the steel battery stand is that it should be painted prior to use. This is both an aesthetic requirement and a safety requirement. The battery stands may be accessed many times a day. The battery stands, therefore, should be painted to be aesthetically pleasing. Most steel battery stands, or at least the brace members of the stands, are painted prior to being shipped on site. During installation, however, the battery stand will likely be subjected to nicks and scratches such that additional touch-up painting is required. In addition to providing an aesthetically pleasing surface, the electrically insulative properties of the paint may protect those working in close proximity to the steel battery stand from electrical shock.
There is also a requirement that the battery stand be anchored to a foundation of the battery plant so as to prevent any movement of the battery stand. The ground mounting device typically depends on the location of the battery plant within the various seismic zones as designated by Bellcore GR63-CORE or other seismic building codes. Currently, for battery plants located in seismic zones subject to greater seismic activity, the battery stand is required to be bolted to the ground with anchor bolts that are mounted in the concrete foundation of the battery plant. A rigid brace, connected to an anchor bolt on one side of the battery stand, may be placed across the top of the battery stand and connected to another anchor bolt on the other side of the battery stand. The rigid brace is typically employed on both ends of each battery stand. Alternatively, the battery stand may be simply secured to the concrete foundation via an L-shaped bracket placed at the base of each corner of the battery stand. Whether using L-shaped brackets or a rigid brace, the usable floor space around the battery stand is decreased by the presence of the anchoring system. Both methods of anchoring the battery stand typically require two to four inches of floor space surrounding the battery stand.
As of December 1998, the Uniform Fire Code was updated to require that a spill containment system be employed to contain the electrolyte leaking from the batteries. Spill containment in battery stands is presently handled by a barrier (generally formed from concrete, steel or plastic) four inches tall and extending one inch beyond a footprint of the battery stand. The use of the barrier requires that the exact location of the battery stand be known prior to installation, such that the barrier may be properly positioned. The permanence of the barrier structure creates a problem with battery stands that are subject to being moved, as the battery plant grows. Further, the barriers are typically sealed with an epoxy that is resistant to the corrosive effects of the electrolyte. The epoxy sealant not only requires an additional step in the set up of the battery stand, but also bonds to the foundation of the battery plant, such that it generally cannot be removed without damage to the foundation of the battery plant. Additionally, once the spilled electrolyte is contained within the barrier, the electrolyte should be removed as soon as possible. The small amount of working space, as described above, may hamper the process of removing the electrolyte from under the battery stand.
Accordingly, what is needed is a composite battery stand having a spill containment system and a ground mounting device that rectifies the deficiencies associated with battery stands of the prior art.
To address the above-described deficiencies of the prior art, the present invention provides, for use with a composite battery stand having a shelf adapted to receive at least one battery subject to leaking electrolyte, an integral spill containment system, a method of containing the electrolyte and a composite battery stand incorporating the system or the method. In one embodiment, the system includes an aperture, located in the shelf, that channels the electrolyte away from the shelf. The system further includes a removable tray, located under the shelf and within a footprint of the battery stand. The removable tray collects the electrolyte via the aperture, thereby containing the electrolyte within the footprint of the battery stand.
The present invention introduces, in one aspect, the broad concept of containing electrolyte, such as acid, spilled from a battery in a battery stand within a removable tray located under and within a footprint of the battery stand. The integral spill containment system advantageously channels the electrolyte away from the shelf containing the leaky battery and collects the electrolyte in the removable tray.
The battery stand is preferably manufactured from a composite material, such as plastic, fiberglass, ceramic, sheet molding compound or structural foam. Of course, other composite materials may be employed as may be advantageous in a particular application.
In one embodiment of the present invention, the shelf includes a flame retardant composite material. In a preferred embodiment, the shelf may be formed from a material that meets or exceeds U.L. 94 V-0. Those skilled in the pertinent art are familiar with a variety of flame retardant materials.
In one embodiment of the present invention, the shelf includes a corrosion resistant composite material. In a preferred embodiment, the shelf is designed to receive a plurality of batteries subject to leaking electrolyte. The shelf is thus preferably resistant to the corrosive effects of the leaking electrolyte.
In one embodiment of the present invention, the shelf includes a recessed section therein to receive the battery. The battery may thus be secured within the recessed section to meet seismic requirements. Of course, other methods of securing the battery in the battery stand are well within the broad scope of the present invention.
In one embodiment of the present invention, the removable tray contains an electrolyte neutralizing material. The electrolyte neutralizing material may thus neutralize the electrolyte to allow safe disposal thereof. In another embodiment, the removable tray contains an electrolyte trapping material. The electrolyte trapping material may trap or absorb the electrolyte to allow safe disposal thereof.
In one embodiment of the present invention, the shelf is a bottom shelf of the battery stand. In this embodiment, the battery stand further includes a spacer and a second shelf that stacks on and interlocks with the bottom shelf. The stand may thus be shipped unassembled and assembled on site with less effort than is ordinarily required by other types of battery stands (e.g., steel battery stands).
In one embodiment of the present invention, the battery is selected from the group consisting of (1) a flooded electrolyte battery, (2) a valve regulated lead acid battery and (3) a gel type electrolyte battery. Of course, other types of batteries are well within the broad scope of the present invention.
The foregoing has outlined, rather broadly, preferred and alternative features of the present invention so that those skilled in the art may better understand the detailed description of the invention that follows. Additional features of the invention will be described hereinafter that form the subject of the claims of the invention. Those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiment as a basis for designing or modifying other structures for carrying out the same purposes of the present invention. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the invention in its broadest form.